The spatially distributed rainfall-runoff model TOPKAPI (TOPographic Kinematic APproximation and Integration) has been widely used for continuous modelling of floods. The model utilises three non-linear reservoir differential equations for the drainage in the soil, the overland flow on saturated or impervious soil, and the channel flow along the drainage network, respectively. The reservoirs derive from the integration in space of the non-linear kinematic wave model. The geometry of the catchment is described by a lattice of cells - the pixels of the digital elevation model (DEM) and their slope - over which the equations are integrated to lead to a cascade of non-linear reservoirs. The parameterisation relies on the digital thematic maps of soil, geology and land use. The model was applied on the upper river basin of Someşul Mare, upstream Beclean (4328 km2) for the 2000-2006 interval: the years 2000-2002 were used for calibration, the model being validated for the 2003-2006 period. The soil and the landuse maps were reclassified with respect to hydrological properties (e.g., soil depth, soil texture, surface roughness, canopy interception). For the time-dependent input, precipitation and temperature from eight meteorological stations have been used. The trial-and-error calibration - based on visually matching the modelled streamflow with the observed one - managed to reproduce the behaviour of the catchment while keeping the parameters within their physically meaningful values. The model reproduced well the behaviour of the streamflow, the peak time, the increase and the recession of the floods. In general, the small floods were overestimated in terms of peak flow. However, considering that only one station (out of eight) is located inside the basin, the first modelling results are very satisfactory.
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